General purpose seamless steel tube by ordinary carbon structural steel, low alloy steel or alloy steel rolling, large output, mainly used for conveying fluid pipe or structural components, this kind of steel manufacturing seamless steel pipe is widely used in hydraulic prop, high pressure cylinder, high pressure boiler, chemical fertilizer equipment, oil cracking, auto axle, diesel engine, Surface quenching or high-frequency quenching treatment for hydraulic pipe fittings. Therefore, according to chemical composition (mainly carbon content), heat treatment process and use of different. Later, it will be found that steel pipes that have not been used for a long time begin to rust in a large area, which also affects the use and quality of steel pipes